BIOL2230 Chapter 25: applied microbiology

Which bacteria ferment lactose in milk, producing acids that curdle the milk?

Spirulina

Saccharomyces cerevisiae

Pediococcus

Leuconostoc mesenteroides

Streptococcus lactis and Lactobacillus

Streptococcus lactis and Lactobacillus

The final treatment of sewage before release into the environment is ______.

skimming

sludge digesting

filtration

chlorination

aeration

chlorination

The first product produced by genetic manipulation and recombinant technology was ______.

amylase

insulin

penicillin

cortisone

insulin

Which organisms are used to make salt pickles?

Propionibacterium and Spirulina

Leuconostoc mesenteroides and Spirulina

Saccharomyces cerevisiae and Leuconostoc mesenteroides

Pediococcus cerevisiae and Lactobacillus plantarum

Streptococcus lactis and Lactobacillus

Pediococcus cerevisiae and Lactobacillus plantarum

Which organism is used to initiate the fermentation of cabbage to make sauerkraut?

Streptococcus lactis

Spirulina

Leuconostoc mesenteroides

Saccharomyces cerevisiae

Propionibacterium

Leuconostoc mesenteroides

A pure or mixed sample of known microbes added to food is a/an ______.

fermenter

flavor inducer

starter culture

aerator

leavening

starter culture

Preventing the incorporation of microbes into food can by achieved by _______.

aseptic techniques for handling meat, eggs, and milk

washing fruits and vegetables

All of the choices are correct.

handwashing and proper hygiene in the kitchen

avoiding cross-contamination of utensils and cutting boards

All of the choices are correct.

Primary sewage treatment includes ______.

aeration

chlorination

sludge digesting

skimming

filtration

skimming

The first stage in making vinegar involves fermentation by ______.

Saccharomyces

Pediococcus

Acetobacter

Spirulina

Gluconobacter

Saccharomyces

Potable water must be ______.

free of all elements

free of pathogens

absolutely clear

sterile

free of pathogens

The source of wild yeasts carried in a biofilm on grapes is the ______.

malt

bloom

wort

must

bloom

What is made by fermenting milk with Streptococcus thermophilus and Lactobacillus bulgaricus?

Sour cream

Cheese

Yogurt

Kefir

Tofu

Yogurt

Nitrates and nitrites are used in cured meats to prevent ______.

infection from fruits and nuts

mold growth

S. aureus food poisoning

botulism intoxication

botulism intoxication

Which of the following activities uses microbial biotransformation?

Production of antibiotics

Alcohol production

Sewage treatment

Yogurt production

Production of antibiotics

All of the following are food-borne pathogens except ______.

Campylobacter jejuni

Staphylococcus aureus

Salmonella

Lactobacillus acidophilus

Clostridium perfringens

Lactobacillus acidophilus

A 100 ml sample of water is filtered through a sterile membrane, and the membrane is transferred to a plate of m-Endo agar. Following overnight incubation at 37°C, 57 green metallic colonies appear. The coliform count is _______.

too numerous to count

57 per 100 ml

5700 per 100 ml

0.57 per 100 ml

57 per 100 ml

Place the steps of the water purification process in order.

Filtration and settling, chemical disinfection, aeration, release into a water reservoir

Chemical disinfection, aeration, filtration and settling, release into a water reservoir

Aeration, filtration and settling, chemical disinfection, release into a water reservoir

Release into a water reservoir, aeration, filtration and settling, chemical disinfection

Aeration, filtration and settling, chemical disinfection, release into a water reservoir

Which of the following statements is true?

Not all microorganisms in food cause foodborne disease.

Microbial metabolism can alter a food to improve its flavor.

Microorganisms can be a food source.

All of the choices are correct.

All of the choices are correct.

You have never seen a jar of jelly contaminated with microbial growth, even though it is used for months at a time. Which is the best explanation?

Jelly has a high osmotic pressure.

Jelly is pasteurized.

A variety of chemicals are added to jelly to make it inhospitable for bacteria.

Jelly is filter sterilized.

Jelly has a high osmotic pressure.

"Live and Active Cultures" on the label of many yogurt products means that _______.

yeast cultures were used to produce the yogurt

the product contains live bacteria

the product may become contaminated by microbes if exposed to air

the product was made by fermentation but then pasteurized

the product contains live bacteria

Sewage treatment processes result in the production of ______, which can be used to make electricity.

hydrogen gas

methane

carbohydrates

nitrates

methane

The most prominent water-borne pathogens of recent times include all of the following except ______.

Salmonella

Norwalk viruses

Staphylococcus

Cryptosporidium

Staphylococcus

Which of the following is not a desired outcome from using microbes in making bread?

Conditioning the dough to make it workable

Giving flavor and odor

Producing ethyl alcohol

Helping the dough rise

Leavening

Producing ethyl alcohol

You have to determine what method is best to prevent the growth of microorganisms in your company's food, ham roasts. This method should be efficient, have a high kill rate, not change the food integrity or taste for the most part, and not add much in the way of chemicals. What would you choose?

Gamma radiation

Pasteurization

Filtration

Freezing

Food preservatives

Gamma radiation

Industrial microbiology is used in the production of ______.

antibiotics

vaccines

hormones

vitamins

All of the choices are correct.

All of the choices are correct.

The products of maltose fermentation in bread-making are ______.

ethanol and water

ethanol and carbon dioxide

lactic acid and water

lactic acid and carbon dioxide

carbon dioxide and water

carbon dioxide and water

You ask the butcher to grind a sirloin roast to be used for hamburger. You family likes hamburgers rare, so you undercook the meat. Unfortunately, within two days they develop the symptoms of gastrointestinal disease: diarrhea, bloating, and vomiting. Which of the following statements best describes what happened?

The meat became contaminated by bacteria from other foods in your refrigerator.

The meat became contaminated by bacteria on the barbeque grill, coating both sides of the hamburger patties.

The meat grinder was contaminated, and bacteria were transferred and distributed throughout the meat.

The meat grinder was contaminated, and bacteria were transferred and distributed throughout the meat.

Biotechnology includes all of the following except _______.

using bacterial antifreeze proteins to protect crops from lethal frosts

using genetically-modified E. coli as a tool to detect cancer

modifying antibiotics with different chemical functional groups to increase their potency

using bacterial insecticidal proteins as a means to combat mosquitoes as disease vectors

modifying antibiotics with different chemical functional groups to increase their potency

Which enzyme is used in medicine as a blood thinner?

Streptokinase

Hemolysin

Cellulase

Rennet

Protease

Streptokinase

The mass, controlled culture of microbes to produce desired organic compounds is ______.

biosynthesis

fermentation

biotechnology

bioremediation

fermentation

Which of the following would be found within the Hazard Analysis and Critical Control Point guidelines for food safety?

All of these are found in the HACCP management program.

Parameters for oyster harvests based on water quality assessment

Precise definitions to distinguish fruit juice from fruit nectar

Temperature requirements for pasteurization of milk

All of these are found in the HACCP management program.

Which of the following statements regarding coliform bacteria is correct?

Coliforms from the human and bovine GI tracts differ, so identifying the specific microbe will indicate the source of contamination.

Petri dishes used to enumerate coliforms are best incubated at 45-48°C.

The presence of Klebsiella is a strong indicator of fecal contamination.

Coliforms derive from the intestinal tract and therefore indicate fecal contamination.

Coliforms derive from the intestinal tract and therefore indicate fecal contamination.

Which step in making beer involves inoculating the wort with a species of Saccharomyces?

Preparing a mash

Wort boiled with hops

Malting

Aging

Fermentation

Fermentation

The disadvantage of batch fermentations, as opposed to continuous feed systems, is that _______.

it is small scale production of a product

there is a limit to the amount of product formed since all materials are added to the fermentor at the beginning

new substrate must be added to the fermentor continuously for the fermentation to continue

the end product is not as pure as the product made by the continuous feed process

there is a limit to the amount of product formed since all materials are added to the fermentor at the beginning

The difference between water purification and sewage treatment is _______.

whether the water source is residential or commercial

the types of microorganisms used for the treatment

there is microbial degradation in sewage treatment, but not in water purification

the amount of air pumped into the water for treatment

there is microbial degradation in sewage treatment, but not in water purification

The yeast used in making bread, beer, and wine is ______.

Leuconostoc mesenteroides

Spirulina

Streptococcus lactis

Saccharomyces cerevisiae

Propionibacterium

Saccharomyces cerevisiae

Which of the following is an example of a secondary metabolite?

Alcohol produced by Saccharomyces during fermentation

Toxin produced by species of Clostridium

Lactic acid made during yogurt production.

All of these are secondary metabolites.

Toxin produced by species of Clostridium

Analysis of a water sample by a series of presumptive, confirmatory, and completed tests that provide an estimate of coliform numbers in the water is called the ______.

coliform count

standard plate count

most probable number (MPN)

membrane filter method

most probable number (MPN)

Which chemical is used in both water purification and sewage treatment to provide long-term disinfection?

Fluorine

Copper sulfate

Activated charcoal

Chlorine

Chlorine

A device in which mass cultures are grown, reactions take place, and product develops is a/an ______.

fermentor

incubator

activator

sparger

fermentor

Preservation of food to limit microbial survival and growth includes _______.

All of the choices are correct.

refrigeration and freezing

high temperature and pressure

pasteurization

irradiation

All of the choices are correct.

Which of the following statements regarding waterborne pathogens is incorrect?

Waterborne pathogens include bacteria, viruses, and protozoans.

Microbes can enter surface water through ordinary exposure to air and soil.

Encysted protozoans can survive in water for long periods without a human host.

Waterborne pathogens are primarily Campylobacter, Salmonella, Shigella, Vibrio, and Mycobacterium.

Waterborne pathogens are primarily Campylobacter, Salmonella, Shigella, Vibrio, and Mycobacterium.